


About Devils and Cats

by Polarnacht



Series: Rare Pair [3]
Category: Lucifer (TV), Shadowhunters (TV), The Shadowhunter Chronicles - Cassandra Clare
Genre: Alternate Universe, Cat Lucifer, Cats will rule the world, Crossover, I Don't Even Know
Language: English
Status: Completed
Published: 2020-05-09
Updated: 2020-05-09
Packaged: 2021-03-02 18:34:10
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,620
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24091414
Author URL: https://archiveofourown.org/users/Polarnacht/pseuds/Polarnacht
Summary: Lucifer escapes hell to run a nightclub and his father is not impressed. He captures Lucifer and turns him into a black cat to punish him. But Lucifer being Lucifer, he takes his fate into his own hands. When he lays eyes on a certain blond Shadowhunter, a devilish plan is forming...
Relationships: Jace Wayland & Lucifer, backround Clary Fray/Jace Wayland
Series: Rare Pair [3]
Series URL: https://archiveofourown.org/series/1733230
Comments: 12
Kudos: 35





	About Devils and Cats

**Author's Note:**

  * For [OliviaLuzia](https://archiveofourown.org/users/OliviaLuzia/gifts).



> Okay, this is definitely something I never thought of writing, but here we are.  
> I totally blame @OliviaLuzia (😘) for this whole story (and WineWednesday. I totally blame WineWednesday as well).

About Devils and Cats

Lucifer was sulking. It was just not fair. Dutifully he had guarded hell for centuries, year after year, month after month, day after day. He couldn’t count the souls he had tortured, tormented and plagued. And as much fun as it had been, after some centuries it just had started to get boring. The screams, the excuses, the pleas – it was just all the same if you heard it over and over again. So he had decided to take a little holiday and escape hell to run a nightclub in L.A. And it had been a hell of a nightclub.

But of course his siblings had to spoil all the fun. His brother Amenadiel had found him and dragged him back to their father. And their father had not been amused, to say the least. As punishment, he had turned Lucifer into a black cat. Lucifer had to spend one whole year in his new cat form before he got turned again.

***

Lucifer mowed annoyed and licked his paw. It really was not fair. Mundanes had been fun when he had been able to sleep with them and mess with them. When he had been able to drink enough to stomach them. But now, without alcohol or any other distraction – they just were dull. Dull, dump and hubristic. They thought they could pet him as if he was a regular stray cat. Some even had tried to feed him with disgusting can food. Can food! For the devil! Having to hunt his own food was kind of humiliating, but better than the evil smelling food the mundanes tried to offer him.

Yes, Lucifer was sulking and he thought he had every right to it, when suddenly he heard a pleasant voice in his ears. He looked up. It was a deep male voice with a slight British accent. He mowed interested. He preferred British over Americans, most just were kinkier. With a smooth jump, he got closer to that voice.

The voice belonged to a handsome boy in his late teens, around twenty if Lucifer had to guess. He was handsome as hell, muscled, blond – and runed. _Shadowhunter._ Luci purred. Shadowhunters were a bit less dull than mundanes, at least they had a purpose. It couldn’t harm to associate with the humans who had a mandate from his siblings. Maybe there was a chance to shorten his punishment. Or something entirely else… And in addition, this particular Shadowhunter just looked delicious.

“Come on, Jace. Let’s get inside.”

So Jace it was. Lucifer purred delighted and strolled closer.

“Wait a second Alec, I think I’ve heard something.” Jace turned around, he still had the enhanced hearing rune activated and something had caught his ears.

“Ooh, look at you, sweetie,” he crooned when his eyes had found the complete black cat at his feet. Only Lucifer’s eyes were shining yellow, his fur was inky black, no single white hair visible.

Lucifer mowed miserably and started to rub his head on the blond’s leg. This display of affection and sorrow never failed with humans. Lucifer would have smiled, but given he was a cat he just pressed his head harder against Jace’s leg. The Shadowhunter knelt down and hold one hand out. Eagerly, Lucifer rubbed his head at the inviting hand. Immediately Jace started to fondle him, tickling him behind his ears and under his chin.

“I think I’ve seen the cat before. I think it’s a stray one,” the girl in the trio cut in.

“Oh no, poor kitty. Are you alone?” Lucifer mowed again, even more miserable than before.

“We need to bring it to the Institute, Izzy. Since Jem has nicked away our Institute cat Church, it felt a bit lonely anyway. Oh look, it has a name tag.”

Izzy stepped closer, also kneeling down beside the cat.

Lucifer purred in approval. Whatever it was, these Shadowhunters had something good going for them. All three of them were insanely hot. Not as hot as the blond, but still.

“Luci it says. I bet he is hungry.” Izzy had started to caress him as well, and at least for now, Lucifer let it slide. Her hands felt good on his fur and as long as the blond kept stroking behind his ears, he was up for anything.

“Yes, he really is thin. We need to feed him.” With that, Jace scooped him up and Lucifer thought that he could get used to the feeling of being carried in those strong arms. Jace pushed his head into his fur, giving him a slight kiss on top of his head. The tall boy, Alec as Lucifer would learn later, just shook his head and rolled his eyes, knowing better than to argue with his siblings.

***

Luci looked judgingly at the Shadowhunters who had assembled around him. He mewed piteously, but refused to eat the food they offered. Luci was aware that he had to teach them properly from the beginning. If he started to eat once this rubbish, they would feed it to him again.

The door opened and one more Shadowhunter entered the room together with a vampire. The vampire strolled over to the girl named Izzy and kissed her lightly on the lips, which earned him a scowl from Alec, an information Lucifer filed away for later. You never knew when such an information could come in handy.

The redheaded girl went straight towards his blond.

“Hey Clary,” Jace greeted her, but not taking his eyes off Luci.

“Hey babe.” _Babe._

The redhead leaned in and kissed Jace. _HIS_ Shadowhunter _._ Luci hissed and glared daggers at the girl. She seemed unfazed by his behavior, but it had the desired effect. Jace leaned down to him again and started to pet him.

“Sh, little one. I know you are hungry. You just have to eat. Come on, just a little bite for me.”

“Maybe he is not used to can food. Maybe he needs real cat food.” From the look on his face, one could tell that as soon as the words had left his mouth, the vampire regretted voicing them.

“You are right Simon,” Alec said gleefully. “And we know someone who can hunt her food.”

“I’m a vampire! I don’t hunt rats or mice.”

“Well, I remember a time where you even ate rats.” The raven boy looked pointedly at the vampire, unimpressed.

Luci purred a little while watching the scene, taking in the small shudder which ran over Simon’s spine at Alec mentioning his past eating habits.

“Please _darling_. He is hungry.“

Lucifer had to admit that Izzy was a master. The puppy eyes she was giving her boyfriend together with the timbre in her voice were impressive. Not to his surprise, the vampire gave in. With a scowl and a curse he turned around and left, but returned shortly with fresh mice.

Delighted, Luci started to eat, purring happily.

***

Luci lay splayed over Jace’s pillow, the sun was shining on his shiny black fur. Lazily he licked his left paw to rub over his head. Jace’s pillow was his favorite sleeping place. It was soft, it was cozy and it smelled heavenly. Or hellishly, whatever word you wanted to choose. The redhead – _Clary –_ had put up a bit of a fight, rambling that pets were not supposed to sleep in beds. A pet. Ha. Luci had shown her what kind of pet he was. He had not watched “Puss in Boots” for nothing several times, he _knew_ how to do perfect kitty eyes. And of course Jace had melted under his stare. Luci purred contently while cleaning himself further, nuzzling his head into the soft, silky sheets which hold Jace’s smell.

He had won this fight, yet he had to win the entire war. He needed the girl to be gone. Normally he had no problems with sharing, but he just didn’t like that one and he maybe liked the blond a bit too much. He wanted Jace to be his and his alone.

For the first couple of weeks he had lain low, just taking in the way everything worked at his new home.

Alec was running the Institute. He was a brilliant strategist, but his weakness was his sense of duty. Luci was certain that he could somehow manipulate him by forging Clave documents or something like that. Alec had a fabulous boyfriend whom Luci befriended instantly, and not only due to Magnus’ own cat eyes.

Luci had learned soon that wherever Magnus was, there was alcohol. His first inebriation as a cat had been rather unpleasant, but at least he had spent it curled up in Jace’s lap. There were worse places to pass your first hangover, but still he didn’t want to repeat this experience too often. So the next time he had gone easier on the alcohol which Magnus had left in his glass, enjoying the tipsiness and lightness the alcohol offered him nevertheless.

Izzy was amazing, she had the whole Institute rapped around her little finger. Luci could admire a good cunning mastermind. Especially the vampire did everything she asked of him, so Luci had never been forced to eat can food again or hunt himself.

No, the other humans were quite all right. No one matched his blond of course, but there was no need to get rid of them. No one but Clary.

***

First Alec had been surprised when he had found Luci in his Office, but Luci made sure to show his best behavior. He didn’t disturb at all, just lay in a corner, bearing the occasional pet Alec gave him. Luci was sure that Alec thought him sleeping, yet his attention was full on Alec and his working pattern. He watched and observed everything the tall Shadowhunter did.

Orders from the Clave appeared mostly with fire messages. Alec sorted them and put them into piles. Things he had to do, things which had to be done by others and so on. The interesting part was when Alec dedicated certain orders and tasks to specific Shadowhunters. Alec piled them all and when he had gone through them, he took them and lay them out in the Ops Center, so that everyone could take their orders for the day and carry on. Only bigger missions were discussed in detail, regular, every-day things were just passed on.

And this was Luci’s chance. He had heard that Alec was not the biggest fan of Clary either and that he thought she was lacking basic training and respect for the ways in which Shadowhunters worked. So it would not be too hard to convince Alec that she had to go get this training somewhere else. Lucifer just had to make sure that Clary didn’t find her orders on some days and therefore missed to complete them. There was not much Alec hated more than unreliability. When the redhead failed her tasks several times, Lucifer was sure that Alec would act.

The other thing was that sometimes the Shadowhunters went against friends of his. A nice demon here, an old acquaintance there. Though Luci was not overly fond of most, there were a few he really liked. He made sure to destroy those orders before Alec had even a chance to look at them. He just had to think whom to blame for it, but there was the second in command, Raj, who was a good victim. Luci didn’t like him anyway.

***

The next time Clary was assigned to two different missions, Luci picked up one with his crawl and destroyed it before the girl had a chance to see it. Of course he had waited until Alec had laid them out, it was important that Alec knew she had not done her duties.

That evening, Luci witnessed the first fight between Clary and Jace.

“But there was only one mission for me, Jace!”

His blond frowned. “Clary, just admit it. You forgot one. That’s ok. But don’t blame my Parabatai. You know how dutiful Alec is. If he says there were two for you, then it is true.”

“But there was only one.” Clary sounded annoyed, but also a bit desperate.

“Do you want to imply that Alec is lying?” The dangerous undertone was not only audible for Luci, the way Clary flinched showed him she had heard it too. She backed off.

Luci yawned lazily and jumped on Jace’s lap to curl into a soft fur ball. He started purring as soon as he felt the blond’s hands in his fur, but he did not fail to glare at Clary.

“I swear that cat doesn’t like me.”

“Oh come on Clary. It is you who doesn’t like the cat, and I really don’t know why. He is such a sweetie.”

At that, Luci purred even louder, rubbing his head against Jace’s strong chest. It was really a pity that cats couldn’t smile.

***

A couple of days later, Luci let another order for Clary vanish. And then another one and another one, always leaving some day in between to not raise suspicion of any kind.

***

Luci meowed contently when he heard the conversation in Alec’s office. Of course he lay on his favorite place, right on top of Alec’s desk. He had started in a corner of the room, but had scooped closer and soon he had started to lay right on top of the desk. At the beginning Alec had seemed a bit annoyed, but giving him his best kitty eyes, he had also won him over. It surely helped that Luci’s eyes looked a lot like Magnus’.

“Clary, enough is enough. Last week I gave you one last chance and again today, you have done only one of the tasks I assigned to you. It seems that you don’t take this job very seriously. Or me. Or both. But it doesn’t matter what it is, I cannot let it slide this time. I turned a blind eye to your behavior now several times because you are Jace’s girlfriend, but I cannot do that any longer. I have assigned you to Wrangel Island to help guard the wards. For now only temporarily, but this highly depends on the way you act now. Guarding the wards is a huge responsibility and you have to answer to Aline. She is a strict but just boss and I hope you respect her more than you respected me.”

Luci purred so loudly now that both Shadowhunters looked at him. Lucifer had heard about Wrangel Island, it was a place near Russia where all unwanted Shadowhunters were banned to. His plan had worked better than expected.

Jace would surely be a bit upset, but Clary and him had fought a lot lately, about Alec, about him – Luci was sure Jace would not be heartbroken over the banishment of his girlfriend. He would make sure to give his blond extra comfort the next few days.

Luci started to clean himself with a lazy yawn and some more purring. Within a couple of weeks, he had managed to practically run the New York Institute. He was quite sure that within the year he had to spend in his cat form, he would run the whole Clave.

And as soon as he had his old human form back, the real fun would begin. He had absolutely no plans to let himself been dragged back into hell again. Not when he had such a gorgeous Shadowhunter waiting for him on earth. A gorgeous and very deadly Shadowhunter, who was surely capable of holding his siblings in check.

Maybe life wasn’t that unfair after all. Maybe you just had to make sure it was fair to you.

**Author's Note:**

> I hope you enjoyed this, uhm, unusual story. If so, thanks for leaving a kudo or a comment 💙


End file.
